Battery including tensioning band bonded to side walls of battery cells by band bonding material

Abstract

A battery (100), in particular a lithium-ion battery, having: a plurality of battery cells (10), which are assembled to form a cell stack and are received in a housing (20), wherein the battery cells (10) are bonded to the base (21) of the cell housing (20) by a heat conductive bonding material (TIM), a plurality of spacer elements (11), wherein a spacer element (11) of the plurality of spacer elements (11) is arranged in each case between two adjacent battery cells (10) of the plurality of battery cells (10), two end plates (22), which delimit the cell stack at the ends, wherein the end plates (22) are connected by at least one tensioning band (23), wherein the at least one tensioning band (23) at least partially surrounds the cell stack circumferentially. To this end, it is provided according to the invention that the at least one tensioning band (23) is bonded to the side walls of the battery cell (10) by a band bonding material.

What is claimed is: 
     
       1. A battery ( 100 ) comprising:
 a plurality of battery cells ( 10 ), which are assembled to form a cell stack and are received in a cell housing ( 20 ), wherein the battery cells ( 10 ) are bonded to a base ( 21 ) of the cell housing ( 20 ) by a heat conductive bonding material (TIM), 
 a plurality of spacer elements ( 11 ), wherein a spacer element ( 11 ) of the plurality of spacer elements ( 11 ) is arranged in each case between two adjacent battery cells ( 10 ) of the plurality of battery cells ( 10 ), and 
 two end plates ( 22 ), which delimit the cell stack at ends, wherein the end plates ( 22 ) are connected by at least one tensioning band ( 23 ) that at least partially surrounds the cell stack circumferentially, 
 wherein the at least one tensioning band ( 23 ) includes a first portion extending along and bonded to side walls of the battery cells ( 10 ) by a band bonding material, 
 wherein the at least one tensioning band ( 23 ) includes a second portion connected to an end plate of the two end plates ( 22 ), 
 wherein the at least one tensioning band ( 23 ) has a slot ( 24 ) formed in a region of connection of the second portion to the end plate ( 22 ), the slot ( 24 ) including two sidewalls that are spaced apart and that extend parallel to a longitudinal axis of the slot ( 24 ), 
 wherein the slot ( 24 ) further includes rounded, bulb-shaped portions ( 25 ) at opposite ends of the slot, and 
 wherein, perpendicular to the longitudinal axis of the slot, the rounded, bulb-shaped portions ( 25 ) extend outside of the two sidewalls and away from the longitudinal axis of the slot ( 24 ). 
 
     
     
       2. The battery ( 100 ) according to  claim 1 , characterized that the band bonding material has heat conductive additives. 
     
     
       3. The battery ( 100 ) according to  claim 1 , characterized in that the band bonding material is the same heat conductive bonding material (TIM) with which the battery cells ( 10 ) are bonded to the base ( 21 ) of the cell housing ( 20 ). 
     
     
       4. The battery ( 100 ) according to  claim 1 , characterized in that the band bonding material has a layer thickness which is greater than a maximum permissible particle size for a residual dirt requirement in the battery ( 100 ). 
     
     
       5. The battery ( 100 ) according to  claim 1 , characterized in that the at least one tensioning band ( 23 ) has an electrically insulating coating. 
     
     
       6. The battery ( 100 ) according to  claim 1 , characterized in that the at least one tensioning band ( 23 ) is connected to the end plates ( 22 ) with material fit, or with form fit or with a combination of material fit and form fit. 
     
     
       7. The battery ( 100 ) according to  claim 1 , characterized in that the at least one tensioning band ( 23 ) and/or the end plates ( 22 ) is/are made from a metal material. 
     
     
       8. The battery ( 100 ) according to  claim 1 , characterized in that battery ( 100 ) is a lithium-ion battery. 
     
     
       9. The battery ( 100 ) according to  claim 1 , characterized in that the at least one tensioning band ( 23 ) is connected to the end plates ( 22 ) by welding, or with form fit or with a combination of welding and form fit. 
     
     
       10. The battery ( 100 ) according to  claim 1 , characterized in that the at least one tensioning band ( 23 ) and/or the end plates ( 22 ) is/are made from steel, stainless steel, or an aluminum alloy. 
     
     
       11. The battery ( 100 ) according to  claim 1 , wherein the first portion and the second portion meet to form an interior angle facing the plurality of battery cells ( 10 ) and an exterior angle facing away from the plurality of battery cells ( 10 ), and
 wherein the longitudinal axis of the slot ( 24 ) is aligned with a vertex of the exterior angle such that a width of the slot ( 24 ) extends into the first portion and into the second portion. 
 
     
     
       12. The battery ( 100 ) according to  claim 1 , wherein the slot ( 24 ) has a length along the longitudinal axis of the slot, a width oriented at 90 degrees to the length, and a depth oriented at 90 degrees to the length and the width and extending into the at least one tensioning band ( 23 ),
 wherein the length is longer than the width, and 
 wherein the length extends away from the base ( 21 ). 
 
     
     
       13. The battery ( 100 ) according to  claim 12 , wherein the plurality of battery cells ( 10 ) and the plurality of spacer elements ( 11 ) are stacked along a stacking direction,
 wherein the at least one tensioning band ( 23 ) has a length that extends parallel to the stacking direction, and 
 wherein the length of the slot ( 24 ) extends perpendicularly to the stacking direction. 
 
     
     
       14. The battery ( 100 ) according to  claim 13 , wherein ends of the slot along the length of the slot are spaced away from side edges of the at least one tensioning band ( 23 ). 
     
     
       15. The battery ( 100 ) according to  claim 13 , wherein the battery cell is configured such that, as a result of thermal expansion of the plurality of battery cells ( 10 ), during use the two end plates ( 22 ) are bent outwards causing a peel strain on the bonding material, and
 wherein the slot ( 24 ) is configured such that a load transfer caused by the slot reduces the peel strain on the bonding material to ensure the reliability of a bonded connection between the plurality of battery cells ( 10 ) and the at least one tensioning band ( 23 ). 
 
     
     
       16. A battery ( 100 ) comprising:
 a plurality of battery cells ( 10 ), which are assembled to form a cell stack and are received in a cell housing ( 20 ), wherein the battery cells ( 10 ) are bonded to a base ( 21 ) of the cell housing ( 20 ) by a heat conductive bonding material (TIM), 
 a plurality of spacer elements ( 11 ), wherein a spacer element ( 11 ) of the plurality of spacer elements ( 11 ) is arranged in each case between two adjacent battery cells ( 10 ) of the plurality of battery cells ( 10 ), and 
 two end plates ( 22 ), which delimit the cell stack at ends, wherein the end plates ( 22 ) are connected by at least one tensioning band ( 23 ) that at least partially surrounds the cell stack circumferentially, 
 wherein the at least one tensioning band ( 23 ) includes a first portion extending along and bonded to side walls of the battery cells ( 10 ) by a band bonding material, 
 wherein the at least one tensioning band ( 23 ) includes a second portion connected to an end plate of the two end plates ( 22 ), 
 wherein the at least one tensioning band ( 23 ) has a slot ( 24 ) formed in a region of connection of the second portion to the end plate ( 22 ), the slot ( 24 ) including two sidewalls that are spaced apart and that extend parallel to a longitudinal axis of the slot ( 24 ), 
 wherein the slot ( 24 ) further includes rounded, bulb-shaped portions ( 25 ) at opposite ends of the slot, 
 wherein, perpendicular to the longitudinal axis of the slot, the rounded, bulb-shaped portions ( 25 ) extend outside of the two sidewalls and away from the longitudinal axis of the slot ( 24 ) 
 wherein the slot ( 24 ) has a length, a width oriented at 90 degrees to the length, and a depth oriented at 90 degrees to the length and the width and extending into the at least one tensioning band ( 23 ), 
 wherein the length is longer than the width, 
 wherein the length extends away from the base ( 21 ), 
 wherein the plurality of battery cells ( 10 ) and the plurality of spacer elements ( 11 ) are stacked along a stacking direction, 
 wherein the at least one tensioning band ( 23 ) has a length that extends parallel to the stacking direction, 
 wherein the length of the slot ( 24 ) extends perpendicularly to the stacking direction, 
 wherein ends of the slot along the length of the slot are spaced away from side edges of the at least one tensioning band ( 23 ), 
 wherein the battery cell is configured such that, as a result of thermal expansion of the plurality of battery cells ( 10 ), during use the two end plates ( 22 ) are bent outwards causing a peel strain on the bonding material, 
 wherein the slot ( 24 ) is configured such that a load transfer caused by the slot reduces the peel strain on the bonding material to ensure the reliability of a bonded connection between the plurality of battery cells ( 10 ) and the at least one tensioning band ( 23 ), 
 wherein the first portion and the second portion meet to form an interior angle facing the plurality of battery cells ( 10 ) and an exterior angle facing away from the plurality of battery cells ( 10 ), 
 wherein the longitudinal axis of the slot ( 24 ) is aligned with a vertex of the exterior angle such that the width of the slot ( 24 ) extends into the first portion and into the second portion.